Yes, paying for premium processing of an L-1 extension will normally speed processing of a SIMULTANEOUSLY-FILED L-2. extension.
But the EAD is a separate filing, and it will do nothing to speed up this application - there really is no way to speed up an EAD other than perhaps the USCIS expedite procedure, and meeting the criteria is difficult (and can actually delay the case if they pull the case to make a determination and determine.that it doesn't meet the criteria). There's a link below to the expedite criteria.
.There is really no way for the Employer to I-9 you, or you to legally work, without an EAD card in-hand. Arguably, there might be a risk acceptance issue if the approval is already issued and the card on its way. The L-2 alone will never be enough.
No it will not speed up the EAD. Without the EAD she cannot work.
Founder and Managing Attorney of Shah Peerally Law Group PC
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