Putting off ttc

We decided we wanted ttc. However I've just been offered a great job with great pay and great maternity benefits. However I have to have worked with the company a minimum of 3 months before i am elegible for them.

I don't start until Feb and I don't to start and then immediately tell them I'm pregnant (on the rare chance that I may fall pregnant the first time) so we'll probably be putting it off another 6 months or so until we start trying. Plus we wanted the baby to born before SOs youngest nephew turns 3 so they are close in age and possibly be able to give my dad a grandchild before his next birthday but that's not going to happen-I know that all sounds ridiculous but..

But I'm itching to start now. How do I contain myself