Thanks for the feedback. I've got 1100 miles in so far this year, over the winter we did a lot of gravel rides (cross bike) so while my mileage is going down during Nov/Dec/Jan, I'm still getting out multiple times a week during that time.

I have a power meter and have done FTP tests and know my zones. Losing weight will help me.

I do get dropped on climbs, and I'm a (relatively) bigger guy so I don't think I will ever stay with a young/skinny guy on the climbs, but I want to be able to stay with them on the flatter sections/rollers. I can produce a good amount of power on the flats and downhill so can make up some of the losses from the climbs then.

Taking a couple of example sections of 1%-2%, grade, I simply can't keep at the pace they are going without blowing up. I don't think they are accelerating to drop stragglers and then slowing down a bit - I think they are just getting up to a speed I can't sustain. I might start in the middle but as we rotate through and I get to the back, my HR is so high that I can't hang on any longer. A lot of these stretches are straight so it's not about skill in turning or drafting (I'm sure I could get better at these, but when I think about where I'm getting dropped, it's because of fitness rather than tactics).

There have been points in the past seasons where I have been able to stay above my threshold and hang on over shorter rollers or over a longer distance, but by then my HR has been high for long enough that I can't hang on for the second half of the ride.

I do suspect the Saturday ride is too fast for good training. That said, I don't have 20 hours a week to ride, so I probably can't do the classic massive endurance base. Maybe I need to do some endurance trainer work during the week, or give up on one of the rides.