+
+ <subsection name="B">Stage "B"</subsection>
+ <news class="beta" date="2019 September 3.">
+ Applicability condition is now parametrized
+ with a generic subset of numbers.
+ </news>
+ <news class="beta" date="2019 June 2.">
+ Applicability condition parametrized
+ with an initial interval of numbers
+ allows λδ-2B to generalize both λδ-2A and λδ-1B.
+ </news>
+ <news class="beta" date="2019 April 16.">
+ Extended (λδ-2A) and restricted (λδ-1B) validity is decidable
+ (anniversary milestone).
+ </news>
+ <news class="beta" date="2019 March 25.">
+ Preservation of validity for rt-computation
+ does not need the sort degree parameter
+ (i.e. no induction on the degree).
+ </news>
+ <news class="beta" date="2018 November 1.">
+ Extended (λδ-2A) and restricted (λδ-1A) type rules justified.
+ </news>
+ <news class="alpha" date="2018 September 21.">
+ λδ-2A completed with
+ confluence of rt-computation and
+ preservation of validity for rt-computation.
+ </news>
+ <news class="alpha" date="2018 June 8.">
+ Behavioral component rt_computation completed.
+ </news>
+ <news class="alpha" date="2018 April 16.">
+ "Big tree" theorem
+ (anniversary milestone).
+ </news>
+ <news class="alpha" date="2018 March 9.">
+ Support for rt-computation completed.
+ </news>
+ <news class="alpha" date="2017 October 17.">
+ Exclusion binder in local environments.
+ Syntactic component updated:
+ syntax, relocation, s_transition, s_computation, static, i_static.
+ </news>
+ <news class="alpha" date="2017 April 16.">
+ Strong rt-normalization
+ for simply typed terms
+ (anniversary milestone).