Attending tribunal alone & how long for dwp reply

I' waiting for my tribunal & am unsure if I should go alone. I'm very capable of presenting my case & communicating with the panel. If I go alone will it make it look as if I don't need any help or support? I'm not sure whether to get my husband to come with me or try to find a disability advocate for support. The initial DWP response to my appeal was that they will contest my appeal "vigorously". I've sent the tribunal services a letter from my gp giving evidence of my health issues which has been passed on to the dwp. Do they have to reply within a certain time limit?