I think people might be a little premature in thinking the PL17 is purely for taking out AWACS and tankers at extended range.
Indeed, I myself would be a little disappointed if they went with such a one-dimensional approach.
Frankly speaking, the US alone has more than 400 tankers. Large numbers of those are going to be deployed to the IndoPac theater in order to support USAF and USN operations against the PLA across vast distances. There is no lack of targets for Chinese LRAAMs and ULRAAMs to choose from, including the PL-17.
Besides, there are plenty - And I mean
plenty - Of US&LC warplanes in the WestPac theater that can rightfully demand the use of LRAAMs and ULRAAMs in the Chinese arsenal.
Even beyond the AEW&C, tanker and fighter aircrafts, you have:
1. Maritime patrol aircrafts like the P-3s, P-8s and P-1s, which the US and Japan have a lot of them, as they are useful for hunting PLAN subs within and around 1IC and even 2IC;
2. ELINT and SIGINT aircrafts like the RC-135s, MQ-4s and RQ-180s, which should also be present in large numbers as well, and will be patrolling and snooping along warzones for PLA transmissions and communications either in the distance (standoff) or stick up close (VLO);
3. ECM and EW aircrafts like the E/A-18s, which can seriously working on messing up PLA radars, sensors, guidance and communication + transmission in the warzone;
4. Airlifters of all types and sizes like the C-17s, C-130s and C-2s, which can be used for rapid warzone resupply of enemy troop positions across WestPac islands; and
5. Last-but-not-least, bombers like the B-52, B-1B, B-2 and B-21, which can either lob standoff missiles from far away, or get in close (VLO) to attack the PLA.
To put it simply - Don't worry. In case Pacific War 2.0 breaks out, China won't be running out of long-range and ultra long-range aerial targets anytime soon.
Looking at the size of the thing and expected future development paths for air combat, I do wonder if it might have exo-atmospheric engagement capabilities.
Sure, hopefully it can be utilized against enemy satellites in the future - And perhaps even certain enemy orbital spacecrafts too (yes, I'm talking about you, X-37).