Help for a noob re: pulsedial signaling

I am installing an Asterisk system for our office - and have a temporary problem. Our telco is insisting that we switch over “right away” to E1 R2 from what they call “12 trunks w/ pulsedial signaling”.
I have purchased our new server and the Digium E1 card, with 2x 8port FXS and 2x 8port FXO gateways from Grandstream. We will be replacing our whole (old NEC) phone switch, but unfortunately our VOIP handsets (shipping from overseas) won’t be here for 2 months.

We have 200 DID numbers which come in over the current 12 trunks.

  1. As a NOOB I don’t really know what “12 trunks w/ pulsedial signaling” really means - are these just FXS POTS lines? (if so how does the DID work ?
  2. Is it possible for me to temporarily switch over to the Asterisk/E1 system and just send the DID calls out my FXS ports to the existing NEC switch until my hand sets get here? or am I better off just waiting for two months.

ps.Please forgive me if this question has been posted in the wrong place or asked and answered already- I looked for a while but some of this technology is so new to me :frowning: and I didn’t even know which terms to search ha!