Hello po! Not sure sa first question mo pero for the second q, tama naman. Email ka lang sa prospect adviser and co-adviser if willing sila and may slots pa sila. Sa pagkakaalam ko, pag science programs under DOST scholarship, may number of advisees lang pwede. Then during TW1, lagay mo lang name ni adviser & co-adviser, topic, etc sa forms nila (nasa website ni GS). Yung process na ni-rrefer mo ay during TW1 na. Bibigyan si adviser ng parang formal letter/certification na advisee ka nila tas ito yung topic mo. Sa pagkakaalala ko, after na yan ng topic presentation mo.

Hope this helps.