TL;DR: The HC 1691 explanatory memorandum states that the Global Business Mobility (GBM) Secondment Worker route will reduce the qualifying overseas employment period from 12 months to six months. The statement of changes implementation table lists Appendix Global Business Mobility paragraphs APP GBM6 to APP GBM8 among provisions expressed as taking effect on 8 April 2026, with transitional wording for applications made before that date. Separate APP GBM1 to APP GBM5 changes are expressed as taking effect on 26 March 2026 in the same implementation section.
The Secondment Worker route is used where an overseas employer has a high-value contract or investment with a UK organisation. The memorandum frames the shorter qualifying employment period as increasing flexibility for businesses while retaining an overseas employment test for integrity.
Commencement and transitional decision-making
For APP GBM6 to APP GBM8 (the implementation list published with HC 1691), the Rules specify that if an application for entry clearance, ETA, permission, a claim, or administrative review is made before 8 April 2026, the decision is taken under the Rules in force on 7 April 2026.
Sponsors and applicants preparing Certificate of Sponsorship timelines should therefore map assignation dates against the 8 April 2026 boundary described in the legal text.
India commitments and Service Supplier (context)
The same HC 1691 package contains GBM Service Supplier changes described in the memorandum as implementing UK–India Comprehensive Economic and Trade Agreement commitments once that agreement is in force, with the memorandum noting that legislation should be in place ahead of a planned end of March entry-into-force timeline. Those provisions sit in a different commencement band (APP GBM1 to APP GBM5 on 26 March 2026 in the implementation list) and should be read from the statement text rather than assumed from press summaries.
Official source
https://www.gov.uk/government/publications/statement-of-changes-to-the-immigration-rules-hc-1619-5-march-2026