You have to meet a few criteria:
As per IRCC:
• Express Entry candidates are responsible for ensuring that the information in their profile is accurate and up-to-date at all times.
• When a candidate is issued an ITA, their profile information and their CRS score are automatically recorded in GCMS.
• If a candidate decides to submit an e-APR, the system automatically transfers the information from their profile to their e-APR for their convenience. The candidate is required to ensure that the information is still accurate before they submit their e-APR to IRCC. If the information transferred from the candidate’s profile is no longer accurate, the candidate must update their application accordingly.
• Processing offices must compare the information in the applicant’s profile at the time of the round of invitations to the information in their e-APR to ensure that the applicant meets the requirements of section A11.2. Note that not all discrepancies should result in a refusal.
You can go ahead with the ITA as the cut off was 75. If you meet the eligibility criteria, you are fine even if your score went down to 317.
Also, your spouse's (dependent) foreign experience does not fetch you any points. Whether you keep them in work history (you will be asked for work ref document) or personal history.
Also, you can change NOC post ITA, and it does not impact your ITA.
I do not see any concerns.