Is this an entry dating back to 2020 or what time stamp does it have?
Also, basically all activities are turned into "completed" except the oath cerenomy?
Ultimately, I would say the line "Probation Forms: sent" is totally irrelevant based on a IRCC Agent conversation I had with when raising the same question approx. 6 months ago when the call center was still reachable by phone

Before the pandemic IRCC used to sent Probation Forms (possibly randomly only) , during the pandemic they stopped it and therefore the entry has become irrelevant.
How much time was between your Decision Made and receiving the Oath invite?