keep only consecutive rows that match the requirement in sas eg - sas

Question

I am new in SAS EG, I would like to know how can I keep only consecutive rows that match my condition. Sample dateset below.
+---------+----------+-------------+-------------+
| Date | Customer | Contract_No | Centre_code |
+---------+----------+-------------+-------------+
| 10Jul19 | AAAAA | AAAAA1234 | 319 |
| 11Jul19 | AAAAA | AAAAA1234 | 319 |
| 10Jul19 | AAAAA | AAAAA5678 | 319 |
| 11Jul19 | AAAAA | AAAAA5678 | 319 |
| 10Jul19 | BBBBB | BBBBB1234 | 515 |
| 11Jul19 | BBBBB | BBBBB1234 | 515 |
| 10Jul19 | BBBBB | BBBBB1234 | 515 |
| 11Jul19 | BBBBB | BBBBB1234 | 515 |
| 10Jul19 | BBBBB | BBBBB11878 | 511 |
| 11Jul19 | BBBBB | BBBBB11878 | 515 |
| 10Jul19 | BBBBB | BBBBB48741 | 511 |
| 11Jul19 | BBBBB | BBBBB48741 | 515 |
+---------+----------+-------------+-------------+
I want only to keep the records that Centre code has changed on the consecutive date per Contract No.
Desire output
+---------+----------+-------------+-------------+
| Date | Customer | Contract_No | Centre_code |
+---------+----------+-------------+-------------+
| 10Jul19 | BBBBB | BBBBB11878 | 511 |
| 11Jul19 | BBBBB | BBBBB11878 | 515 |
| 10Jul19 | BBBBB | BBBBB48741 | 511 |
| 11Jul19 | BBBBB | BBBBB48741 | 515 |
+---------+----------+-------------+-------------+
Desire output
+---------+----------+-------------+-------------+
| Date | Customer | Contract_No | Centre_code |
+---------+----------+-------------+-------------+
| 10Jul19 | BBBBB | BBBBB11878 | 511 |
| 11Jul19 | BBBBB | BBBBB11878 | 515 |
| 10Jul19 | BBBBB | BBBBB48741 | 511 |
| 11Jul19 | BBBBB | BBBBB48741 | 515 |
+---------+----------+-------------+-------------+

Answer 1

Based on a clever solution posed under Replicating values in SAS by group
proc sort data = have;
by contract_no date;
run;
data changed;
merge have
have (firstobs = 2 rename = (date=date_next code = code_next customer=customer_next contract_no = contract_no_next));
retain output_next_flag 0;
if (contract_no = contract_no_next and date_next - date = 1 and code ~= code_next) then do;
output_next_flag = 1;
output;
end;
else if output_next_flag then do;
output;
output_next_flag = 0;
end;
else output_next_flag = 0;
keep date customer code contract_no;
run;