As kg.jadu said, I don't think submitting RA/TA experience at this point would be at all useful. But you can try. The best that you can hope is maybe to have them consider your TA/RA up to the date of application, but even that is pushing it in my opinion.
What's for sure, though, any work experience gained after your date of application won't be considered, as TyrusX has mentioned earlier in this forum. Not sure though if they consider his TA/RA experience that he added much later after his application date (he emailed Ottawa directly to add TA/RA, but I don't think they said anything about whether they added it to his experience). He (TyrusX) already got his medical, but he already got above 67 points, even before including TA/RA, so there is no way to tell for sure (maybe his CAIPS notes now would reveal whether they w