SIGMETTACParserBase and AIRMETTACParserBase currently have lots of duplicated code. For maintainability code should be deduplicated as much as possible.
Most of the code could probably be moved to a common superclass.
Even though we have the issue with FreeBuilder builders extending an interface (https://github.com/fmidev/fmi-avi-messageconverter/issues/77), it might be worth implementing a common superinterface for SIGMET.Builder and AIRMET.Builder (like MeteorologicalTerminalAirReportBuilder for METARImpl.Builder and SPECIImpl.Builder).
SIGMETTACParserBaseandAIRMETTACParserBasecurrently have lots of duplicated code. For maintainability code should be deduplicated as much as possible.SIGMET.BuilderandAIRMET.Builder(likeMeteorologicalTerminalAirReportBuilderforMETARImpl.BuilderandSPECIImpl.Builder).