Customer Numbering Sequence

As per Doc ID 397212.1 and following an upgrade from 11.5.10.2 to 12.2.5 the cache size was set at 1000 causing newly created Customer Numbers to increment by 1000 at a time. This has caused our numbering to jump from 75000 in November to 353500 in May, despite only a few hundred customers having been set up.

We have reset the cache size to zero as per doc 397212.1 and numbers are now incrementing by 1 as expected. However we now have huge gaps in our numbering. If we reset the sequence to recommence numbering from 75001, will the system prevent duplicate numbers being created where numbers already exist between 75000 and 353500?