select v_beg.service_id, v_beg.timestamp as t_beg, min(v_end.timestamp) as t_end, v_beg.status
  from ( -- все начала событий:
         select *
           from t t0
          where not exists 
                (
                   select first 1 null
                     from t t1
                     where t0.service_id = t1.service_id
                       and t0.timestamp > t1.timestamp
                       and t0.status = t1.status
                     order by t1.timestamp desc
                )
       ) v_beg
  join 
       ( -- все кончала событий:
         select *
           from t t0
          where not exists 
                (
                   select first 1 null
                     from t t1
                     where t0.service_id = t1.service_id
                      and t0.timestamp < t1.timestamp
                       and t0.status = t1.status
                       order by t1.timestamp
                )
       ) v_end
    on v_beg.service_id = v_end.service_id
   and v_beg.status = v_end.status
   and v_beg.timestamp <= v_end.timestamp
 group by v_beg.service_id, v_beg.status, v_beg.timestamp 
order by service_id, t_beg

select service_id, MIN(timestamp) as t_beg, max(timestamp) as t_end, status
  from (
         select t.*
              , ROW_NUMBER() over(PARTITION BY service_id, status order by timestamp) - 
                ROW_NUMBER() over(PARTITION BY service_id order by timestamp) as grp_id
           from t
       ) v
 group by service_id, status, grp_id