I brewed a chocolate milk stout almost 4 weeks ago and I had intended to bottle this evening. I realised that I don't have any bottle caps and I have visitors arriving tomorrow and won't get a chance to bottle for another 2-3 weeks. Is it ok for me to leave it in the primary bucket sitting on the yeast for that long or do I need to rack it to a secondary (something I've never done before)? If I do need to rack it, my carboy is a 6 gallon and there will probably be quite a bit of head space for a 5 gallon batch, will this cause any problems?