Review the changed duties and applicable occupation rather than assuming the original qualification analysis remains sufficient.
Keep the current role visible
Retain the amended offer and explain the new responsibilities. An unchanged employer or salary does not settle the effect of a substantive change.
Start well before the expiration date rather than in the final weeks, since gathering updated evidence and confirming the role still matches the original basis takes time. On the US side, ask which month the company actually needs the advisor in the field, and count backwards through the offer letter, the credential documents and the chosen application route. Discuss with the employer whether the proposed start date can flex if either step takes longer than expected, and avoid resigning from current arrangements in Canada before the visa step is resolved. Work backwards from the first date the applicant must lawfully be doing the work, then insert the steps that have to precede it: the structural review, any restructuring the employer agrees to, the credential evidence, and the employer letter. The immigration step can often be completed relatively quickly once the qualification documents and the employer's letter exist, and it should be scheduled behind the licence. Transcripts covering several years of study take longer than a single diploma, and reissuing a corrected employer letter takes the employer's own time on top of that.