This is one of those things that, for the time being, everyone is looking at the possibility of the use of quantum entanglement as means of relaying information error free and over enormous distances at greater than light speeds:
Repeated experiments have verified that this works even when the
measurements are performed more quickly than light could travel
between the sites of measurement: there is no lightspeed or slower
influence that can pass between the entangled particles. Recent
experiments have shown that this transfer occurs at least 10,000 times
faster than the speed of light; this merely establishes a lower limit
to the speed — according to the formalism of quantum theory, the
effect of measurement happens instantly.
But short of quantum entanglement for purposes of communication, we currently have no means of relaying information faster than light, and they all come with various drawbacks, mainly the signal strength and with it required power for communications signals to traverse without loss of data over such vast distances. So, of course, for any missions at lightyear distances, you'd want your probe to be as autonomous as possible, possibly have some form of Artificial Intelligence (AI) onboard, at least somewhat controlling the probe to avoid any obstacles it might encounter.
Similar semi-autonomous systems are already in use with several unmanned probes that we sent in space, for example the Rosetta spacecraft has the ability to avoid close proximity obstacles, something that will likely need as it starts closing the distance to the 67P/Churyumov–Gerasimenko comet it is chasing and when it approaches the Sun increases its coma and tails, with possible debris chipping off it. Even being merely around 1 Astronomical Unit (AU) away is still distant enough to cause communications delay that is utterly unmanageable for avoiding collisions from the Earth in real time.
So having more advanced AI in place and have our probes eventually 100% autonomous, not depend on having to communicate with us over distances in the magnitude of light years, and do their work completely independent of our constant control of their functions is, arguably, just a few decades shy from materializing and certainly within the reach of even our current technology. That ought to be a lot faster than we'll be able to develop any interstellar drive technology getting us there by the time our probes are still expected to operate and anyone here still ready to listen to data it transmits back.
I guess what I'm trying to say is the communications delay might not matter so much, if we learn to design around this obstacle with the use of AI, which seems to advance a lot faster than drive technology needed to reach other stars in a reasonable timeframe is. And when quantum entangled communications will be possible, all these drawbacks in communications delay and power requirements needed to produce strong enough signals for us to eventually pick them up will be gone.
As for the off-chance of encountering yet unmet sentient beings out there that would be technologically advanced enough to detect our presence - all of this is a matter of opinion, like with the rest of dealing with the unknown. My opinion (take it as such) is, that luckily for us, chances of encountering another civilisation in their counterpart to our 16th century development and though are extremely remote to say the least, so any proper protocols that should be in place in the eventuality we'd encounter previously unmet entities should be a lot easier to achieve than what popular culture would have us believe in science fiction movies and literature.
If they'd be any less technologically advanced, you'd likely pass by undetected, or our presence dismissed as something that the civilisation you encountered can relate to. And if they're same or more technologically advanced than we currently are, they will know well enough that it's a robotic probe they've detected, as such a proof of intelligent life elsewhere in the vastness of the Universe, and will likely rejoice and have a golden record with greeting from the Earth to place on top of their charts. And if they won't and are combatant in nature, they will most likely be involved with themselves too much to pay attention to some other civilisation, light years away, and by the time they could, their civilisation will be back to stone ages.
I don't think we should preoccupy ourselves with how advanced some theoretical civilisations that aren't ours and are light years away might be, and rather more frequently look back and reflect on ourselves in which of the two directions described we are heading. My 2 cents. ;)