Differential Backup understanding in Azure SQL Backup and Restore

Question

Hi Team,
I am having a basic Azure sql server and few databases in it

we are having the retention policy as below
PITr-7days
Diff. backup frequency - 12 hrs
Weekly LTR-4 weeks

Differential backup captures only those changes which were done since the last full backup

PITR - point in time is like full backup of the database at that point and differential backup is like all changes done between the latest PITR time and for every 12 hours till date?

we have LTR backup as below
Backup time (UTC) Backup expiration time (UTC)
2022-04-27 14:08 2022-05-25 14:08
2022-05-04 14:00 2022-06-01 14:00
2022-05-11 14:03 2022-06-08 14:03
2022-05-18 14:05 2022-06-15 14:05

when we select any db to restore its showing the earliest restore point ie 18th may and current restore time for the new restoration db.
do we doesnt have the privilege of selecting differential backup? what if the transactions also done between that after that 12 hrs of differential backups.are they missed out or how they are captured

Answer 1

Just to make things sure... you are talking about an Azure VM with SQL Server installed on it and you are using Azure Backup to create those backups... right?
As "Automated Backup (for SQL Server 2016+)" doesn't provide "Differential Backups"...

And from your explanation it looks like you even can't see any differential backup in your list... are you sure those backups were taken?
LTR isn't relevant here.

Can you send a screenshot of you backup policy that shows us what you have configured?