ah ... you have a board .... I assume it was just that metal can only.
about that thingi i can not comment , honestly ... as it unclear how it constructed ..
i build a while ago , like 4 years ago ,F ref , on the same OCXO can, it was significantly thermally isolated, consumed 25 ma
after a while, year or so in ON state , drift was ... hm ... in 4 month approx. , from precise 10 ... to around 9.999 999 998 5
sooo basically 5 10-8 per year around ... ( i'm right?)
received today OSC5A2B02, was curious about jitter .... seems nothing ...
I may consider , super duper high jitter was incorrect measurement :
i'm wait 60 seconds , till snapshot , that 7th rise from the trigger

forgot to say .... that high P-P, due to GPSDO, reference , as the circuit truing to constantly push-pull OCXO adjustment , if you run fa-2 for at least a week , internal oscillator would be reasonable steady, and hook gps to input, you may see as 2 last digit constantly jumping up or dowm, merely depend on gpsdo algorithms adjustment ...