After found a very rare early 1st execution Aquastar Regate with Felsa 4000N in the “container case” a service was needed.
So sent to THE man for these kind of watches – Richard Askham in the UK.
He did all well and tried hard to fix the pusher, that doesn´t switch back to zero not perfect from time to time but he was “beaten by the watch”. So maybe that pusher (and the “container case” design of the watch) caused the switch to the “standard” case soon after the 1st execs as we can see on the serial numbers.
You can read his post about working on the watch here.
More to read about the early “5 dot” Regate with Felsa 4000N you find here.
Please join Richs phantastic website with a lot of information about some very nice vintage watches he repaired and serviced.