Timestamps :-

1. Insertion timestamps: Nobody can change because it is append only timestapm

2. Value timestamps: backend officer can change the value. It can be a future value and it can be a past value as well 

backdated transction : Usually in case of interest accruals. 

By default, Postings in the Vault System are expected to be created and applied immediately in the

vast majority of use cases. Each accepted Posting will generate a new balance record that is

persisted in time order, thus creating a balanced time series. What this means is that you’re able to

look back to view historical balances for your customers’ accounts at any point in time in the past. All

consequent fund calculation and movement, such as fees, interest, will be affected by the updated

balance.

However, it’s expected that you will have exceptional use cases that require you to be able to add

postings to a past date and time. This is possible in the Vault System.

To facilitate this use case, Postings in Vault hold two timestamps:

The insertion_timestamp is when the posting was inserted into the ledger. This should be used for

reporting purposes, e.g. GL reporting. The insertion_timestamp can only be set by the core ledger, ie.

Vault. The value_timestamp represents when the posting was ‘effective’ from, and is used to calculate

balances. It can optionally be set when generating new postings via the API.

You’re able to create backdated postings by setting the Value timestamp to a previous point in time.

Vault will insert these backdated postings to the ledger and will retroactively recalculate past

balances from the new postings up to the current time.