No, they can designate it all as OE, and only the last 75% of it is withheld by PBS. If you read the page 23-10, Section 23.D.X. you'll see that there are no restrictions other than the block hour limit and 75%. The company designates it all, and the senior F/Os via PBS get the first 25%. The rest are withheld.

They can can designate every LCA awarded trip as OE up to the block hour limit based on guys finishing training in that bid month. Look at August 767 sim schedule. 21 New Hire NYC 7ER complete training and 30 New Hire 7ER with no base assigned finish. That's potentially 51 New Hires going to NYC times 75 block hours each. At an ALV of 84, that's up to 45.5 lines of time if all trips are hard time. There is nothing in the TA language that prevents the company from designating all of that for OE. The first 25% of those trips go to senior F/Os on the PBS bid, and the rest are withheld by the company (about 33 regular lines worth). So sorry. That 33 relative seniority cascades down to the last F/O on reserve.