2022 and yes.

Whenever it comes I just hope they stay in the budget category and dont Go premium like canyon, they will basically have that whole segment for themselves!

Excellent.
I'm pretty close to pressing the button on a P-Series. (Nearly did a couple of weeks ago but dithered and then the correct size had gone).
With little likely racing this year (and my main race in the Highlands so I'll use the road bike + bars) I may hold off to next year - a sensibly priced Trinity with disc brakes would be a great option.

For 2021 Giant is selling a single build option for the Trinity and a single option for the Trinity Pro alongside the remaining 2020 stock. In total the options are lack luster and this would suggest to me Giant has something in works and didn't want to kick out a ton of frames before the new options came available. Given the issue that everyone is having sourcing parts for 2021 bikes Giant is also conserving resources on limiting the build options. Specialized did something very similar prior to the launch of the Shiv Disc where they phased out the Shiv Tri over a 1-2 year period. I would not be surprised to see the new bike officially launch this year but it will be the '2022' model and given the current state of the industry who knows when it will hit showroom floors.

Given the way Giant is going with I think you are right about discs. Giant (via their subsidiary brand CADEX) is already fully invested in aero tubless disc wheels and I would be surprised if they were to stick with rim brakes when they are have committed this deeply to disc wheels across all their other bikes. 2021 may also be the last call for the rim brake TCR which from a historical bike evolution perspective is not an insignificant milestone.