D-Link uses hardware and region codes. typically refers to a hardware revision (e.g., DSL-2750U ME1 ) and a specific regional firmware base (Middle East/Asia/India). The 30 (or 3.0) indicates the firmware version branch.
Firmware version ME_1.30 (specifically the later builds like B038_K8B_0K_ME3G-00-4424) introduced several critical fixes and features: dlink dsl2750u firmware me1 30 download best
Updating to ME_1.30 is a straightforward but delicate process: How to update your D-link router (DSL 2750) - step by step 18 Aug 2019 — D-Link uses hardware and region codes