Unbonding twice during same period results in longer thawing period for first unbonding?

When unbonding twice during same period, graph only shows longer unbonding period. Question is explained the below example…

If I unbond 100 GRT on 1st of month and have to wait 28 days then GRT is ready for withdrawl on 29th. But, if I unbond another 100 on 2nd, why does it show 30th for all 200 GRT instead of 100 on 29th and 100 on 30th?

The timer for undelegation from the same indexer resets every time you undelegate during the thawing period.