Leagues have different requirements according the grade level criteria established by England Hockey and South Central.
For SBHC, the following levels applies:

SBHC		M1	M2/M3/M4	M5/M6	Juniors
Teams		L1	L2	L3/L4/L5	Hornets
	Grade 1	Grade 2	Grade 3	Grade 4	Grade 5
Level of accreditation required	Level 3	Level 2	Level 1 Assessed	Level 1 Assessed	Level 1 Unassessed
Acceptable minimum accreditation (where agreed by the ALMC)	Level 2	Level 1 Assessed	Level 1 Assessed	Level 1 Unassessed	No formal accreditation required
Who conducts appointments	NPUA	AOC(1) where possible, otherwise clubs	AOC(1) where possible, otherwise clubs	Clubs	Clubs
Can umpires be switched at half time?	No	No	No	No (unless agreed by the ALMC(2) & the opposition captain)	Yes

(1) AOC - Area Officiating Committees
(2) ALMC - Adult Leagues & Competitions Committee

Notes:

Cup matches have different rules, some have appointed umpires, others each team provides one umpire. It will be case-by-case during the season
Juniors and Men's O50 leagues is TBC