Your tier 2 ICT time does not count towards the 3 years. You will start again from zero. Tier 2 ICT issued after 6th April 2010 does not lead to ILR based on 5 years in any visa combination.
Immigration rules part 6a - 245BF(C)(iii)(i)
https://www.gov.uk/guidance/immigration ... sed-system
245BF.Requirements for indefinite leave to remain
To qualify for indefinite leave to remain, a Tier 1 (Exceptional Talent) Migrant must meet the requirements listed below. If the applicant meets these requirements, indefinite leave to remain will be granted. If the applicant does not meet these requirements, the application will be refused.
Requirements:
(a) DELETED
(b) The applicant must not fall for refusal under the general grounds for refusal, and must not be an illegal entrant.
(c) All of the following requirements must be met:
(i) The applicant must have spent a continuous period of:
(1) 3 years lawfully in the UK, if their last endorsement by a Designated Competent Body was under that body’s criteria for “exceptional talent”, as set out in Appendix L, or
(2) 5 years lawfully in the UK, if their last endorsement by a Designated Competent Body was under that body’s criteria for “exceptional promise”, as set out in Appendix L;
(ii) The applicant must have, or have last been granted, leave as a Tier 1 (Exceptional Talent) Migrant.
(iii) The relevant continuous period in (i) must have been spent with leave either as a Tier 1 Migrant (excluding as a Tier 1 (Graduate Entrepreneur) Migrant or Tier 1 (Post-Study Work) Migrant) or as a Tier 2 Migrant (excluding as a Tier 2 (Intra-Company Transfer) Migrant).
