L1B individual Extension with Canada option

[MJVision]

Hi All,

Currently I am in US. My L1b individual Visa and I94 is expiring in next 4 months and i want to file for Extension. My sponsor suggests to file from Canada (i think which will) result in new L1B blanket filling. I am having following doubts:
1) Is it better to file new L1b blanket visa from Canada instead of filling extension from US?
2) Possibility/chances of getting approved "new L1b blanket visa from Canada" VS "filling extension from US for existing L1B Individual visa"?
3) If we already have my case adjudicated from USCIS for L1B individual, is it good option to go for new L1B blanket filling from Canada?

Regards,
Sar