Daily Suggested Workout progress level lost/reset last week after 18 months of use

I have been using daily suggested workouts for more than 18 months. The interval and long runs have been progressing forward. Long runs to over 2 hours. The base run progressed to 38-40 minutes.

Last week the suggested workouts REDUCED to:

- a base run of 30 minutes [previously 38-40 mins]

- a long run of 33 minutes [previously around 2 hours]

- a recover run of 26 minutes [previously 30 minutes]

- an anaerobic run of 42 minutes (5 x 1min @3.45min/km) [previously 55-70 minutes]

I'm guessing it has lost my progress and reset to beginning levels.

I was finding the pace of progress quite effective. Taking into account sleep/stress/workouts etc. I'm finding this very frustrating, as I'm now back to programming my own sessions.

Has anyone else experienced this? Even more interesting, for me, is there a way to restore this to my previous levels, or at least close to them?

Garmin Forerunner 945LTE

Software Version 7.11