When erev Pesah falls out on Shabbat, Bedikat Hametz is done on Thursday night, followed by recitation of the Bitul. 

• On Friday morning, we burn any hametz that is not necessary for Shabbat.  Although the hametz may be burned all day, it is customary to burn it before midday (as on other erev Pesahs) so as to be in the habit of burning it at this time in the years to come. 
• However, the Bitul is not recited after the burning because we will still be eating hametz on Shabbat. 

Shabbat Meals 

• At the Friday night and Shabbat morning meals, we must wash and eat bread. Therefore, great care must be taken with the bread to make sure that no crumbs remain or fall on the floor. 
• Children must be supervised very well when they eat the bread to make sure that they do not leave the table or drop crumbs. 
•  Although hametz is permissible through the fourth hour* on Shabbat morning, many difficulties can arise, i.e., cleaning the hametz dishes and pots, etc., on Shabbat; therefore, it is strongly advised not to eat hametz for these meals (other than the bread).  All the food should be kosher for Passover and prepared in Passover pots. To further help make matters easier, these meals should be eaten on paper (or plastic) dishes and cutlery that can easily be disposed of.  It is important to remember to flush the crumbs away before throwing these dishes away. 
• The morning meal must be eaten before the end of the fourth hour*.  Therefore, one must pray early so as to finish the meal by the fourth hour. 

After the Shabbat Morning Meal 

•  After the meal, all hametz crumbs must be destroyed by flushing it down the toilet. If regular plates were used, they must be thoroughly cleaned of any hametz and put away with the hametz dishes. 
•  The Bitul is recited one hour* before midday.  However, the word hefker is not recited on Shabbat. 

Seudah Shlishit 

• At the proper time for eating Seudah Shlishit we are not allowed to eat hametz or matzah.  Fruits and vegetables may be eaten instead and care should be taken not to overeat so as not to spoil one’s appetite for the Seder. 
•  It is preferable to eat two meals in the morning, before the end of the fourth hour*. There should be a break between the two meals so that Bircat HaMazon will not be said in vain.  Even though someone may have eaten two meals before the fourth hour, he is still obligated to eat Seudah Shlishit at the proper time (after 6½ hours*).

*The hours are derived by dividing the day into twelve parts, from dawn until nightfall.