L1 --> H1. Can we specify Start Date?

[consider]

As the window for h1 filing is still open, while filing a COS from L1 to H1. Can we specify the start date with h1 employer?

Reason I am asking this is, if COS is filed now premium processing with start date say 1st March. With Premium processing we will know the result in 15 days and then can serve notice period with L1 employer and join the new H1 Employer.

Is this possible?
If not, how do people manage? I mean, one day you get your COS approved and without getting your service certificate you go on to h1 employer?
or Is it like after you get your COS approved you will get new I94 with start date of 2 weeks/some days later?

Thanks in advance.

[shervin143]

Yes. It is possible to file the H1B petition with a start date of upto 6 months in future.

[consider]

Thanks so much, it helped a lot. Will ask H1 Employer to file with a future start date.