There is an IP pool of Container allocation type with at least one leased IP address. Despite the leased IP addresses, the IP pool allocation type can be changed.
After the allocation type change all used IP addresses disappear from the list of leased IP addresses.
It is impossible to switch the IP pool back to Container allocation type, the following message appears
Unable to change allocation type: some of the IP addresses are currently being used
Even though all of of the pool IP addresses are used by Container type subscriptions only.
The behaviour is classified as the software issue PBAS-29771 and has been fixed since OBAS 4.5.3
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