when NXT block chain does get "shrunk" will it remove previous version of an alias or retrain all the previous URI's in the alias?

For example:  Jan 1   alias "helloworld" = "test1"   and then Jan 10th updated "helloworld" = "test2" ... will the test1 record be completely removed from the block chain?

Also same question about AM.  Will previous AM's get removed once the blockchain is shrunk?