Some timings are approximate.
It might be possible to arrange a meeting, towards the end of the conference, with the Conference Secretary to discuss organisational details and queries, and to arrange for the transfer of the mailing list . The people who attended the previous conference will have been given the Invitation Leaflet. All others on the mailing list could now be sent it. The Invitation Leaflet should be publicised. This might be the time to print the formal conference stationery.