I have tennets renting my house who are subletting in violation of the lease and are currently 8 days late with rent (the lease only allows for 7 days) although They say I can come pick up the rent today.
How can I get them out of the house legally? Can I give 30 days notice for their violations, or is there a process I must follow? The lease is in Texas.
Thank you!

They are subletting and the lease doesn't allow subletting? If so, give them 30 days notice. If they don't vacate, then you will have to go through the eviction process. Check with your local court as to what that is,

I, personally, would go pick up the rent. After cashing the check I would then serve them a 3 day (unless your lease specifies less) notice for breach of lease. That gives them 3 days (or whatever your lease's notice period is) for the original tenants to move back in, or you file for eviction.

The other option is to approach the new tenants and attempt to put them under lease - if you think they are desirable.

Change your lease so that late charges start on the 4th (new law just passed in TX that you can't start charging late fees until the 4th.) There's no reason to give them until the 7th to pay.

How long have the sub-lessors been there?