TP just announced a re-org of the OPO-LIS vv shuttle, to less frequencies (~13/day) and from mostly ATR to Airbus.
https://www.tapairportugal.com/en/me...ss-Release-708
Unless you have specific needs, just don't bother with ASR, as it's basically paid if you want a seat and not worth it for the short 30 min hop.
See this post from Palal which is pretty current. Check-in T-36 you can OLCI, T-3 go back for free seat assignment.