Really need some help here... have an asset that should have been capitalised in Nov, is there a way to go back and begin capitalising from that date? I believe it's wrong accounting practice but in any way, how would we go about doing this so it capitalises from Nov onwards... I'm assuming we would need to open the prior periods for this to happen? Using the fixed asset management bundle

You can create the fixed asset record from the Bill/JE if your FAM is configured to do so, else just create the fixed asset record and enter the start date (Nov 2022). NS will plan the depreciation based on your start date, depends on your company/accounting team if you will reopen periods or not, but most likely unless it is material you will post all of the missed depreciation into the current period. You can do this be running depreciation for the past periods, FAM will still pick up posting that are eligible, but post to an open period when depreciation is ran for a closed period.

thanks @Alex K another question, is there a way to reduce the lifetime of a new asset type that I create so it automatically reduces per month? i.e. have an asset lifetime of 34 months this month and next month when a new asset is created with that asset type... it would reduce to 33 months then following month to 32 months etc... so in total all assets would finish at the same time regardless of when it was created?

That would require a script/workflow to automate, seems like a lot of work IMO. You could create an asset type for each Asset Lifetime you want (Not ideal) or likely just edit the Asset Lifetime when creating fixed assets. Likely depends on the volume of fixed assets you are creating that need this changing asset lifetime.