The current record is 1920 days, held by PewDiePie. However, T-Series is only 200 days away, so as it stands they will pass the record sometime in July 2024.

The most likely way for T-Series to not break this record is if MrBeast, currently at 223 million subscribers, surpasses T-Series (currently at 256 million) before T-Series would break the record. (But someone else theoretically could!)

Resolves to whatever Wikipedia says as long as they are seemingly accurate.

(This is pretty objective so I will bet on this question)