Is there any legal limitation on when you should start using the new certified ESIR in Serbia?

If you already have a certified ESIR solution in Serbia and have changed the fiscal version of the ESIR software, you should apply for a new certification and get approval to use the new software. Once the recertification is complete, the question is: when are you obligated to switch to the new version? This answer depends on two cases.

As it is the new version of the same ESIR, you can use the previous version without a time limit. You can schedule the transition to the new version at your convenience.

An exception to this rule would be if the certification of a new version was carried out due to an established deficiency of the previous version, that is, due to a mandatory change stipulated in the Technical Requirements or a subsequently established error of the previous version. In that case, the need to start using the new version would be related to the identified deficiencies.