VS307/308

Hi
Hope someone can help.
Does anyone have any explanation as to the recent (temporary as I understand it) renumbering of some of the US East Coast flights? VS7/8 has been operating on and off as VS307/308 and VS23/24 as VS323/324,and similarly with VS19/20 as VS319/320, as well as an additional rotation as VS325/326. I know that sometimes because of a change in fight times people like BA can re number flights such as BA169 from PVG becomes BA1169.
Can anyone shed any light on these?
Thanks in advance
AJ
Hope someone can help.
Does anyone have any explanation as to the recent (temporary as I understand it) renumbering of some of the US East Coast flights? VS7/8 has been operating on and off as VS307/308 and VS23/24 as VS323/324,and similarly with VS19/20 as VS319/320, as well as an additional rotation as VS325/326. I know that sometimes because of a change in fight times people like BA can re number flights such as BA169 from PVG becomes BA1169.
Can anyone shed any light on these?
Thanks in advance

AJ