Hi Daniele,
Yes chrono module seems to have mixed parts (jumper springs 8270 and 8705 are the heavier ones of an early cal11 but the hammer 8220 is close (in order to hold the hammer cam jumper) as in the cal12.
See here:

http://onthedash.com/docs/ChronomaticMovements.html

From the image I cannot see if the oscillating pinion is the bimetallic one (cal11) or the stainless steel one (cal11i and 12).

An easy way is to check two things:

- if the date changes between 23.45 and 24.00 is for sure an early cal11 beating at 19800 vph;
- if instead the date changes slowly between 22.00 and 24.00 then could be a cal11i or a rare transitional cal12 with nickel plated chassis, at this point you need to put the watch on the timing machine and check the beat: 19800 vph is cal11i while 21600 vph is cal12.

Hope this helps.

Best.

Gianluca