Hi Sam, I have received an offer from HMRC for CSA. I would like to know how fast and what career progression we can hav

CSA starts at Administrative Officer (AO) grade. For most jobs that are promotions (i.e anything EO grade or higher), it is usually a requirement that you have completed your 6 month probation. There are already lots of jobs on the Civil Service Jobs website at various grades, but there are more that you can apply for when you enter the Civil Service, as they are only open to internal applicants. When you join the Civil Service, you can link your work email to your existing Civil Service Jobs account to be able to see them.

Thank you so much for the insight Sam !

I am waiting for a start date from CSG in Portsmouth how long does this usually take please?

There's no real set time frame, it will depend on lots of different variables.