I'm planning on a spring full. I've successfully done pfitz 18 55 for two pr's, and 12 55. I like the plan, have not had issues with it, but in the quest to keep my training novel, and. Not increase the volume too much (55/60) is really as much as I have time, commitment, and recovery for at 45 with a family, job, and home life. Are there 18 or so week plans I can look at that have similar distance / intensity as the 18/55?
Also, if I do 18/55 again there are a number of tune up races which are always plotted for Saturdays.... Why? Almost no races are on Saturday. From a training plan perspective shouldn't they know this and design a plan with regular racing in mind? How do you all deal with these Saturday tune up races. In the past I've just done individual tt's with a target time on a known race course where it's more accurate that watch based 'gps' distance.
This way I'm simulating the 6.3/13.3 that happens in real races and not the shortest distance that watch based tt's can do.
For your first question, have you looked at Jack Daniels' training plans? https://fellrnr.com/wiki/Jack_Daniels
He has a variety of plans in his book, some easier, some tougher, some 18 weeks, some in 4 week sets that can be repeated. Workouts on quality days are a bit complex, but totally manageable with a smartwatch.
For your second question, most of the races in my area are on Saturdays, though marathons are usually on Sundays. Even then, when I've used the pfitz plans, I've had to adapt to fit a race into my schedule that fell on the wrong week or else do a tt on my own. I think Pfitz briefly describes somewhere in the book how to add races to the schedule, like how many days to taper before and after. Pfitz seems to value getting race day experiences, so I would guess adjusting the schedule to fit a race in is preferable to a tt.
Good luck with your spring full!