Oil and Gas Field Extension

Please explain when they say field was extended out. First numbers same but have additional A, B, C Exp.: 2001-A 2001-B etc/

Same section/ same survey lease # changes Exp: 1986 Lease # 7890 BBB Production 2002 Lease# 1892 CCC Production Different operator???

Why won’t RR commission give any info other than well productive in regards to section or lease #