Psionicists can train themselves to rise in level without the assistance of a higher-level character as an instructor. A character may only attempt this kind of meditation when eligible to rise in level (she has gathered enough experience points to advance to the next level) and is seeking to train herself.
Self-training for level advancement takes a total of 20 days. If the character has access to a tutor who specializes in the same discipline and is at least two levels higher in level then herself, she need not make any progress checks. Otherwise, she can train herself but must make progress checks as normal.
Training to advance a level is the easiest of the meditations, since the character has already accumulated many of the skills she will need later on. After all, she already earned the necessary experience points for the next level. Because of this, she need not start over if she is interrupted and suffers no ill effects from missing three progress checks in a row.